This invention relates to methods for controlling a cooling circuit for an internal combustion engine, in particular of a motor vehicle, in which the cooling circuit has at least one coolant pump for controlling coolant flow and a radiator in which heat is exchanged between the coolant and an air flow which can be controlled by a fan and wherein the speed of the coolant pump and the speed of the fan may be controlled as a function of a required temperature value of the coolant.
An arrangement for controlling the coolant temperature of an internal combustion engine for use in a motor vehicle is described in German Offenlelegungsschrift No. 38 10 174 in which the internal combustion engine is connected by separate coolant pipes to a heat exchanger in the form of a radiator and to a coolant pump. The coolant circuit is completed by a coolant connecting pipe between the heat exchanger and the coolant pump. A controllable-speed fan for producing an air flow through the heat exchanger is associated with the heat exchanger. In addition, that arrangement includes a control unit which controls both the coolant pump for circulating the coolant and the fan for producing the air flow through the heat exchanger as a function of a variable required temperature value of the coolant. In this system, the operating parameters of the internal combustion engine are taken into account in the determination of the variable required temperature value.